Well, for one thing we are all fatter, and the prevalence of depression in obese people has been found to be much higher than in healthy weight people. We are a

Well, for one thing we are all fatter, and the prevalence of depression in obese people has been found to be much higher than in healthy weight people. We are also more sedentary. For another, most of us spend a lot of time on social media, the usage of which, at least for some demographics, has been strongly linked to depression. Also, due to screen usage and even LED lights interfering with melatonin production, we are getting one hour less sleep on average. That is actually an unreported crisis if you look into the effects of losing even one hour of sleep a night consistently. Then there is the deterioration of social structures and "third places" such as church, clubs, and other social gatherings, which are shown to reduce depression.